divisions of the ocean floor - · pdf filethe ocean floors can be divided into four major...

DIVISIONS OF THE OCEAN FLOORDIVISIONS OF THE OCEAN FLOOR

The ocean floors can be divided into four majorThe ocean floors can be divided into four majorDivisionsDivisions The continental shelfThe continental shelf The continental slopeThe continental slope The deep sea plainThe deep sea plain The oceanic deepsThe oceanic deeps

Other major and minor relief features areOther major and minor relief features are Ridges , hills, sea mounts, guyots , trenches and Ridges , hills, sea mounts, guyots , trenches and

canyons , etccanyons , etc

Continental shelfContinental shelf The continental shelf is the zone around aThe continental shelf is the zone around a

continent , extending from the line of permanent immersion to continent , extending from the line of permanent immersion to the depths at which there is a marked increase of slopes to the depths at which there is a marked increase of slopes to greater depths. The continental shelves are covered with greater depths. The continental shelves are covered with variable thicknesses of sediments brought by rivers, glaciers etc. variable thicknesses of sediments brought by rivers, glaciers etc. The depths varies between 65m to 300m.The depths varies between 65m to 300m.

DIVISIONS OF THE OCEAN FLOORDIVISIONS OF THE OCEAN FLOOR

The ocean floors can be divided into four majorThe ocean floors can be divided into four majorDivisionsDivisions The continental shelfThe continental shelf The continental slopeThe continental slope The deep sea plainThe deep sea plain The oceanic deepsThe oceanic deeps

Other major and minor relief features areOther major and minor relief features are Ridges , hills, sea mounts, guyots , trenches and Ridges , hills, sea mounts, guyots , trenches and

canyons , etccanyons , etc

Continental slopeContinental slope

The continental slope connects the The continental slope connects the continental shelf and the ocean basins. The continental shelf and the ocean basins. The slope boundary indicates the end of the slope boundary indicates the end of the continents . Canyons and trenches are continents . Canyons and trenches are observed in this region. The depths vary observed in this region. The depths vary between 200 to 3000m. between 200 to 3000m.

Deep sea plainDeep sea plain

Deep sea plains are gently sloping areas of theDeep sea plains are gently sloping areas of the

ocean basins. These are the smoothest region ofocean basins. These are the smoothest region of

the world. The depthsvarybetween3000to6000m. the world. The depthsvarybetween3000to6000m.

Oceanic deeps or TrenchesOceanic deeps or Trenches

These areas are the deepest parts of These areas are the deepest parts of the oceans. The trenches are relatively the oceans. The trenches are relatively steep sided, narrow basins. They are some steep sided, narrow basins. They are some 3-5 km deeper than the surrounding ocean 3-5 km deeper than the surrounding ocean floor.floor.

Minor relief featuresMinor relief features

Mid-oceanic ridgesMid-oceanic ridges

A mid-oceanic ridge is composed of A mid-oceanic ridge is composed of two chains of mountains separated by a two chains of mountains separated by a large depression.large depression.

Sea mountSea mount

● A submarine mountain or peak rising more A submarine mountain or peak rising more than 1000m above the ocean floor is than 1000m above the ocean floor is known as a sea mount.known as a sea mount.

guyotsguyots

It is a flat topped sea mount. More than It is a flat topped sea mount. More than 10000 sea mounts and guyots exist in the pacific 10000 sea mounts and guyots exist in the pacific ocean alone.ocean alone.

Submarine canyonsSubmarine canyons

These are deep valleys , they are sometimes These are deep valleys , they are sometimes found cutting across the continental shelves and found cutting across the continental shelves and slopes.slopes.

Atoll Atoll

These are low islands found in the tropicalThese are low islands found in the tropical

oceans consisting of coral reefs surroundingoceans consisting of coral reefs surrounding

a central depression. a central depression.